The Medrano catchment is located in the extreme north of
the city, with a total catchment area of 3.641ha, of which 1813ha are found
in the capital city and the other 3569 in the area of the Buenos Aires province.

Its main flow path (currently culverted along its original natural course)
is an extension of the open watercourse that runs through the Villa Martelli
army fields in the district of Vicente López. It then flows into the
city at Sarmiento park, after flowing through the streets; Ruiz Huidobro,
Melián, García del Río (through Saavedra park) and Comodoro
Rivadavia until it discharges at the Rio de la Plata, traveling a distance
of approximately 6km in a southeast-northeast direction.

The drainage network in the province area is different to that of the city
because it doesn’t have one collector sewer but has many main branches
that drain the following sub-catchments:

· Sub-catchment with a contributing area to the entry point of the
main trunk sewer at General Paz.
· Storm water network of Tres de Febrero
· Storm water network of the San Martin district that flows into
the Medrano stream in its open air stretch before entering the city.
· Secondary sewer of Constituyentes street and its contributing network.
· Villa Martelli sewer and its contributing network.
· Contributing sub-catchment to the secondary sewer of Holmberg street
· Contributing sub-catchment to the the secondary sewer of Chivilcoy
street.

In general terms the drainage network consists of a series of sewers with
an average density of approximately 30m/ha. The main trunk sewer of the drainage
network is characterized for having nearly rectangular sections with a width
that varies between 7 and 20m and an average height in the order of 3.5m.
It flows into Rio de la Plata through an open channel with a varying section
width of 30m to 300m.

The trunk sewer has a practically constant base gradient of 2 in 1000 until
approximately Cabildo Avenue where it begins to decrease to values of in the
order of of 1 in 1000. Meanwhile the average gradient of the secondary sewers
is in the order of 4 in 1000 at the headwaters, decreasing to 1 in 1000 where
it discharges into the culverts of Medrano.

The presence of green areas is small and is limited to approximately 15%
of the total catchment area. The Medrano stream catchment is characterized
for having its green areas distributed throughout all of its contributing
area. This is not the case for the Maldonado and Vega catchments.

The main features that characterize the Medrano stream are due to:

· The existence of a stilling basin in Villa Martelli that corresponds
to the open channel section of the Medrano stream.
· The presence of General Paz Avenue with important longitudinal development
crossing the entire catchment. This acts as a barrier to overland flow.
· The existence of a hydraulic control from the entry point at the
province towards the city. This control consists of a rectangular sewer with
a width of 7.2m and a height of 3,2m. This forms a barrier to inflows from
the province when flooding occurs.
· The existence of more than one inflow point from the province to
the city.